The present invention relates to a baffle board construction which, pursuant to insulating the attic space of buildings, partially blocks the openings which connect the attic space and the overhanging eaves. More particularly, this invention relates to a baffle board construction of the type described which provides that insulation blown into the attic will extend to the outermost perimeter of the walls and will not be lost into the eaves; which insures that proper ventilation is maintained between the attic space and the eaves after insulation; and which is a standard unit facilitating use with different type roofs, including truss and offset roof constructions, and roofs using framing members of different widths.
In many building constructions, the roofs are made using framing members which include horizontal ceiling joists and inclined roof rafters which are connected in the area of a top plate forming the top surface of the building walls. The roof rafters extend outwardly beyond the building walls and form hollow eaves. Openings between the roof framing members and openings in the underside of the eaves ventilate the attic space of the building to the atmosphere so that heated air can escape from the attic.
It has become customary to insulate the attic space of these buildings with a particulate insulation material which is blown in place. In that case, it is necessary to install baffle boards in the openings between the roof framing members to form a dam to prevent insulation which is blown in place from being lost into the eaves. These baffle boards, which may be constructed of cardboard or the like, are positioned in the openings and may be secured to the roof framing members and/or the wall top plate such as by stapling.
It is important that insulation in the attic space of buildings extend as close to the outermost periphery of the building walls as possible to minimize heat loss at the perimeter of the building. Thus, it is important that the baffle boards be positioned to allow the insulation which is blown in place to extend as close to the outside perimeter of the walls as possible.
It is also important that adequate ventilation be maintained between the attic space and the eaves after insulation for proper air circulation between the eaves and the attic space. This is necessary in order to prevent heated air from being trapped in the attic space which would cause the rooms beneath the ceiling to remain excessively warm during warm weather, and to prevent moisture buildup in the attic space during the winter. Thus, it is important that the baffle boards used do not themselves completely block the openings between the attic space and the eaves, or allow the insulation to completely block these openings.
Still further, there are a number of "standard" building roof designs, including truss and offset roofs. In a truss roof, the roof rafters and ceiling joists are aligned (coplanar) and joined at abutting edges using suitable connector plates. In an offset or "stick built" roof, the ceiling joists are fastened to one side of adjacent roof rafters. Furthermore, offset roofs sometimes have ceiling joists fastened to both sides of each roof rafter such as in the area of load bearing walls, referred to as a double offset roof. In addition, all of these "standard" roofs can be constructed using different sized framing members.
It will be appreciated, therefore, that the size and shape of the openings in which the baffle boards are to be positioned are different for each of the identified "standard" roof constructions, and for each of those constructions which use different sized framing members. If a different baffle board is required for each of the different roofs, it is then necessary for the baffle board manufacturer to make, and for the installer to stock, a wide variety of different baffle boards. In addition to the obvious inconvenience, this results in higher manufacturing and inventory costs, and ultimately higher prices to the consumer.